Electrically operated siren



Aug. 17, 1937. MlLEs 2,090,138

ELECTRICALLY OPERATED SIREN Filed Nov. 14, 1927 2 Sheets-Sheet l W/ 27 #735 42 y 3 20 55 U Pi g5 INVENTOR. LESTER H. MILES A TTORNEY.

Aug. 17, 1937. H. MILES ELECTRICALLY OPERATED SIREN Filed Nov. 14, 1927 2 Sheets-Sheet 2 INVENTOR. H. M/L ES LESTER A TTOR NE Y.

55 may be secured by any suitable means.

Patented Aug. 17, 1937 PATENT OFFICE ELECTRICALLY OPERATED SIREN Lester H. Miles, Los Angeles, Calif.

Application November 14, 1927, Serial No. 233,094

3 Claims.

This invention relates to electrically operated sirens.

The general object of this invention is to provide an improved motor driven siren wherein the motor brushes may be retracted from engagement with the armature.

Another object of this invention is to provide an improved motor wherein the brushes are normally out of engagement with the armature and "wherein means is provided for causing the brushes to engage the armature when current is directed to the motor.

A further object of the invention is to provide a motor of the class described for driving the rotor of a siren so that when the current is cut ofi from the motor the siren rotor and motor armature may rotate freely without the friction of the brushes on the armature.

Other objects of this invention will be apparent 0- from the following description taken in connection with the accompanying drawings wherein: Fig. 1 is a side elevation of my improved motor driven siren.

Fig. 2 is a central vertical longitudinal section 25 through the siren shown in Fig. 1 and a portion of the motor.

Fig. 3 is a section taken on line 33 of Fig. 1 with the siren rotor removed, showing the bolts which secure the motor to the siren.

' Fig. ,4 is a central vertical section of one of the motor brush actuating members showing the brush in a normal or retracted position.

Fig. 5 is a diagrammatic view of the electrical hook up of the motor shown in Figs. 1 to 4 in- 3 5 elusive.

Fig. 6 is a central vertical longitudinal section through a siren and a portion of a motor showing a modified form of brush actuating means.

Fig. 7 is a section taken on line 'l-'l of Fig. 6

40 showing the modified form of brush actuating means, and

Fig. 8 is a diagrammatic view of the electrical hook up of the motor and brush actuating means shown in Figs. 6 and 7.

" In Figs. 1 to 5 inclusive I have shown my invention as embodied in a motor driven siren indicated generally at ID. The motor which is shown as secured to and adapted to actuate the siren is indicated generally at H. The siren in- 5o.cludes a casing l2, having a rotor l4 mounted therein. The motor l0 may be of usual construction except for the brushes and includes an armature l5 and an armature shaft I6 having a reduced end portion l! on which the siren rotor I4 The that as many of these devices may be employed in a motor as may be desired.

The devices 20 as shown each comprise a housing 22 positioned in a recess 23 in the motor case and removably secured to the motor case by any suitable means such as by cap screws 24. The housing 22 is provided with a removable cap 25 having an aperture 25 therethrough and having mounted thereon a solenoid winding 21.

Mounted within the housing 22 I provide a brush retainer 28 made of an insulating material and provided with a removable cap 29 which is likewise made of an insulating material and includes a projection 30 which is positioned in the aperture 26 of the cap 25 and has a solenoid core 3| secured thereto in any suitable manner.

A coiled spring 32 surrounds the brush retainer 28 and bears against the bottom of the housing 22 and the under side of the projecting edges of the cap 29 and normally urges the cap 29 against the bottom of the housing cap 25 as shown in Fig. 4.

The bottom of the brush retainer 28 is provided with an aperture 33 in which is mounted a brush 34 having a head 35 thereon which is of a greater circumference than the circumference of the aperture 33. A coiled spring 36 normally urges the head 35 of the brush 34 into contact with the bottom of the brush retainer as shown in Fig. 4. Any suitable means for conducting electricity to the brush 34 may be used but in the accompanying drawings I have shown a wire 38 secured to the brush and passing out through an aperture 39' in the cap 29 and the solenoid core 3|.

As shown in Fig. 5 the wire 38 connects to a feed wire 39 which is connected to one pole of a battery 40 or any other suitable source of supply. The feed wire line 39 includes a control switch indicated at 4|. From the opposite pole of the battery 40 a wire 42 is connected to the field of the motor which is indicated at 43.

One end of the solenoid winding 21 is connected by means of a wire 44 to the feed wire 39 through a condenser 45 and the other end of the solenoid winding is connected by means of a wire 46 to the wire 42 through a condenser 41, thus it will be seen that when the control switch M is closed as shown in Fig. the current will flow from the battery 39 through the feed wire 39, through the condenser 45 to the solenoid winding 2'! and thence through the wire 49, through the con- 5 denser 4V to the Wire 92 and back to the battery 40. As the solenoid windings 2'1 are energized the core Si is pulled from the position shown in Fig. 4 to the position shown in Fig. 2, thus forcing the brush retainer 28 towards the armature I5 and allowing the brush 34 to contact with the armature.

When the brush 34 contacts with the armature I5 the current from the battery will pass through;

the switch t! is opened the solenoid windings 21 cease to be energized and the spring 32 forces the brush retainer to a retracted position as shown in Fig. 4, thus disengaging the brush 34 from the armaturel 4- whereupon the flow of current to the motor will be cut off. 1

In- Figs. 6. 'land 8 I have indicated a motor at 59 which includes a modified form of brush actuating means. The motor 59 is shown as secured to andadapted to operate the siren indicated generally at 5! and which includes a casing 52 and a rotor 53 mounted therein. The various elements of the motor 59 may be of usual construction except for the brushes and includes an armature 54 andan armature shaft 55 on which the siren rotor 53 is secured in any suitable manner. The armature shaft 55 is preferably supported in a bearing 56 in the siren casing in addition to being supported in a bearing 5'! on the motor, but

if desired the bearing 59 may be omitted.

Motor brushes 58 in this modified form are shown as mounted in housings 59 which are positioned in apertures 69 in the motor housing. Each of the brushes 58 includes an enlarged head 5 l which is positioned within the housing 59 and prevents the brushfrom being displaced from the housing. Each of the housings 59 is provided with 'a detachable cap 62 and within the hous- 5ings' I provide a. coiled spring 63 which bears against the cap 92 and the head 6| of the brush and tends to urge the brush head against the bottom of the housing.

For actuating the brushes 58 I provide a.pair of-rings95'and 69 which are-rotatable in'grooves 51 and 98 in the motor casing. The rings 65' and 96 are of like construction and are each split as at 99 to facilitate assembly. The'rings 65-and 59 i are preferably connected by cross bars J0 and are each provided with ears 1 I. in which there is-provided an angular slot 12. Pins 13-extending, from the brush housing 59 are, positioned in-the f slots-l2 of each ring. The ring is provided with an arm 79 to which a coiled spring is attached which normal-1y tends to hold the arm 14 against the stop 16 so that the rings will force the pins 73 of the brush housings to the end of I the slots TF2 farthest from the; center of the armature thus raising the brushes out of contact twith the armature. I I 'For moving the ring 65 in theoppositedirece tion to move the brush housing pins 13 in'the slots 72 towards the armature I provide a sole-' noid Tl including Windings'lB and a core 19. The 7 Ecore l9 is-pivotally secured to a link 89 as at;8l and the link 80 is pivotally and slidablyiconnected to an arm 82 of the ring 65 as at 83. v V a For moving the ring 65 inthe opposite directionitd move the brush'housing pins 13 in the slots l2 towards'the" armature Iprovidea solethence to the armature i5 whereupon the motor 119 will operate to rotate the siren rotor M. When noid 71 including windings l8 and a core 19. The core 19 is pivotally secured to a link 80 as at 8| and the link 89 is pivotally and slidably connected to an arm 82 of the ring 65 as at 83.

For energizing the solenoid windings as shown in Fig. 8 a wire 85 connects one end of the windings 18 through a condenser 89 to a feed wire 81 which includes a control switch 88 and is connected to one side of a battery 99. The other end of the solenoid windings is connected by a wire 99 through a condenser9l to another feed wire 92 which is connected to the other side of the battery 89.

The feed wire 87 connects to the field of the 'motor 59 and the other feed wire 92 is connected wire 99, through the condenser 9| to the wire 92 and back to the battery 89. As the solenoid windings 78 are energized the core 19 will'be moved and cause-the rings 65 and 66 to move against the action of the spring 15 tocause the rushes to move into contact "with the armature 54.- When the brushes contact with the arm-ature the'current from the battery will pass through the feed wire 92 and wires 93 to the brushes and thence to the armature 54 whereupon the motor 50 will operate to rotate the siren rotor 53.

When the control switch 88 is opened the solenoid windings l8cease to be energized and the spring 15 then moves the rings 95 and 66 to cause the brushes 58 to move out of contact with the armature 54 whereupon the flow of current to the motor will be cut ofi.

In using my sirens by moving the brushes out of contact with the armature, the frictionof the as a fly wheel to maintain the momentum of the siren rotor when the current to the motor is discontinued so'that the siren rotor coasts at an operating speed for a long time after the current to the motor is cut on.

From'the foregoing description it will be apparent that I have provided a novel motor driven siren which is compact, durable and eficient in use. I

Having thus described myinvention, I claim! 1. In apparatus of the class described, an electric motor having an armature shaft and a commutator, a housing enclosingthe commutator including an end wall rotatably receiving said shaft, brushes supported within the housing for movement to and from engagement with the commutator, a brush .operating device rotatably mounted within the housing coaxially of the shaft between said wall and the commutator and including parts adapted when said device is rotated in one direction to lift the brushes from engagement with the commutator, said device when rotated-in an opposite direction serving to' release the brushes for'return to engagement with the commutator and means for rotating saiddevicein opposite directions.

2. In apparatus of the class described, an electric motor having an armature shaft and a commutator, a housing enclosing the commutator including an end wall having a bearing thereon rotatably receiving said shaft, brushes supported within the housing for movement to and from engagement with the commutator, a brush operating device rotatable within the housing upon the exterior of said bearing and adapted when rotated in one direction to lift the brushes from engagement with the commutator, said device When rotated in an opposite direction serving to release the brushes for engagement with the commutator, means within the housing for rotating said device in one direction, and separate means for rotating it in an opposite direction.

3. In apparatus of the class described, an

electric motor having an armature shaft and a commutator, a housing enclosing the commutator including an end wall adjacent one end of the commutator, brushes supported within the housing for movement to and from engagement with the commutator, a brush operating means rotatably mounted within the housing coaxially of the shaft between said end wall and the commutator and including parts adapted when said device is rotated in one. direction tomove the brushes from engagement with the commutator, said device when rotated in an opposite direction releasing the brushes for return to engagement with the commutator, and means for rotating said device in opposite directions.

LESTER H. lVHLES. 

